After rumors and various leaked lists, the official lineup for Lollapalooza 2012 has been announced. The annual 3-day festival will be headlined this year by The Red Hot Chili Peppers, Black Sabbath, and Black Keys. There’s no short of urban acts as Frank Ocean, The Weeknd, J. Cole, Wale, Santigold, Yuna, Macklemore & Lewis, and Childish Gambino will all perform at this year’s event taking place on August 3-5 at Grant Park in Chicago, Illinois.